Variable-power brake



Jan. 16, 1923. 1,442,250.

L. E. C HA M 0 N VARIABLE POWER BRAKE.

FILED MAY 2. 1921. 2 SHEETS-SHEET 1.

Jan. 16, 1923.

L. E. CHAMON. VARIABLE POWER BRAKE.

FILED MAY 2, 1921 4 2 SHEETS-SHEET 2.

Patented Jan. 16, 1923.

UNITED STATES LOUIS EUGENE CHAMON, or PARIS, FRANCE. I

VARIABLE-POWER BRAKE.

Application filed May 2, 1921. Serial No! 466,013. I

To all whom it may concern Be it known that I, -LOUIS EUGENE GHA- MON, engineer, citizen of the French Republic, residing at Paris, Department of the Seine, in France, and having P. 0. address 5 Avenue du Pere Lachaise, in the said city, have invented certain new and useful Improvements in Variable Power Brakes; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to brakes for railway vehicles and its object consists in obtaining a device which, when operated by any known means, acts on the brake-' blocks in such way that the pressure exerted by them on the wheels when they are braked. is automatically and without need of any external aid 2. function of the total weight (tare and load) of the vehicle braked.

The accompanying Figures 1, 2 and 3 show clearly in what way the invention has been carried out; in these figures; V r

Fig. l is a section of the device; Fig. 2 an example of carrying. out the device when controlled by a vertical brake piston; Fig. 3 another example controlled by a horizontal piston.

In these figures-the device is applied by way of example to a bogie-vehicle.

The reference numerals are the same-in all the figures for the same elements.

Referring to Fig. 1, the lower part of the centre pin socket consists of twomembers l and 2, the former-fixedto the bogie' bolster, the latter capable of vertical dis placement upwards with respect to the former on which it rests in normal conditions. A cylindrical guide ring 3 secures the transmission of the horizontal efforts from one to the other of the said members 1 and 2, and two flat guide rings 4 prevent any relative angular displacement of the said members. I g Y The bogie spindle 4 is pivoted at 5 at its lower part to a lever'6 with two arms movable in a vertical plane and each connected through links 7 and 7 and bell crank levers 8 (these being pivoted at 9 to the b'ogie bolster) to the axles 10 of the vertical levers 11 operating the brake blocks. Springs 12 suitably arranged keep the whole mechanism in tensionand provideforv taking up automatically any playat the joints.

Between the joint head 5 of the bogie spindle 4? and the member 1 fixed to the bogie bolster is interposed an elasticappa= ratus 13 erected with a certain stress. -Further, this spindle 4? is providedat 14 with a washer constituting a collar and making contact with the lower part of the member 2. y v i I The upper portion of thebogie spindle is of reduced diameter and extends through the member 2 of the socket and the member 2 of the vehicle frame, and the upper end of said reduced portion is threaded to receive a nut ll. 7 I

The upperfend of one of the vertical levers is connectedin the ordinary way by more or less complicated transmission gear to the piston of a brakecylinder 15 (Figure 2) which, when it operates, first brings the brake blocks into contact with the wheels, the bogie rigging moving from the position a to the position b and the lever 6 osoil- I lating around its pivoted centre 5'with the spindle 4 of the centre-pinsocket.

This contact having been efiected and the piston of the cylinder continuing its stroke, the'same bogie rigging moves from the position b to the'position 0, the lever 6 then pivoting no longer round 5, but round those'joints 9 which are situated away from the control. I

Therefore at 5 there operates on the spindle 4 of the centre pin socket a vertical effort transmitted partly to the elastic apparatus 13 which is compressed, partly to the member 2 which, together with the body and the load, takes an upward movement accompanying the movement of the" piston and ending with it, when the said piston meets the cylinder end or any other stop arranged for the purpose.

The elastic apparatus 13 being so constructed that at the end of its movement it opposes a resistance equal to the weight of the bogie and its axles increased, if necessary, in a certain proportion, in order to take into account the inertia of. the moving parts,.-the" total efi'ort exerted at 5 is equal to half the total weight of the vehicle (bogie and its axles body 7} load) increased by the additionabove mentioned.

On the other'hand, this total effort is evidently proportional-dike 'any other transmitt-ed by any member of the rigging--to the pressure exerted 'by the brake blocks on the wheels, so that, as-stated at the beginning of this specification, this pressure is in fact a function of the weight of the vehicle in question on the rails, whatever amount of load it may carry. 7

This result evidently supposes that under all circumstances the stroke of the piston of the brake cylinder is completely effected, or, in other words, that the effort exerted by the operative fluid (atmospheric air or compressed air) on the said piston isalways at least equal to that required to produce the lifting of the loaded body 'to the maximum, the excess available being taken up by the reaction exerted at the end of the stroke by the stop (cylinder end or other).

If however this condition should not he realized and if, owing for example to insuf fieient pressure in the cylinder, the stroke of the piston were limited to that required to bring about the contact of the brake blocks with the wheels (movement from the position a to the position b), there would be no great inconvenience, in this case in fact the brake would merely act as an ordinary brake, that is to say the braking effort would be a function of the pressure in the cylinder and not then of the total weight of the vehicle.

Figure 3 shows an arrangement similar in principle to that above described but with a horizontal cylinder for compressed'air and bogie rigging operating on inside instead of outside brake blocks; in this case the effort transmitted from one vertical lever to the other is a compression instead of a tension.

The transmission may take place through links and bell crank levers similar to those in Figs. 1 and 2 and constructed to effect like them the lifting up of the body, or as shown in Fig. 3 by a combination of members jointed together not by axles but by knife edges kept in contact by the action of side springs 12.

This latter construction is merely mentioned as an example of the various constructions which may be assumed in carrying out the type of brake in question, these constructions depending on the special c0nditions of each case; number of brake blocks, and their position with respect to the wheels, space available, etc.

Similarly, it is immaterial whether the cylinder is operated by vacuum (Fig. 2) or by compressed air (Fig. and in the, latter case whether it is single or double acting.

Finally, the same brake might also be applied to two-axled vehicles. For each of these axles, the suspension arrangements would then be fixed to a frame independent of the body, the rigging also fixed to this frame being constructed in such way that when the brakes are put on, it causes simultaneously, as in the above mentioned case of bogie-vehicles and by the same mechanism, the compression of an elastic system integral with the body and the lifting of the body and load.

Claims:

1. In combination, a railway car body, a truck for the same, a vertically movable bogie spindle connecting said truck and body, a brake rigging, resilient means associated with said spindle and acting to force the same in one direction, a stop for limiting the vertical movement of said resilient means in one direction, and a connection between the-brake rigging and said bogie spindle adapted, when the brake operated, to cause a vertical movementofthe spindle, compression of said resilient means and the raising of the body and load in such manner that the total braking effort, other things being equal, varies with the total weight of the vehicle automatically and in accordance with a predetermined law.

2. In combination, a vehicle truck, a vehicle body supported by said truck, a bog'ie spindle connecting the body and truck, a stop through which the spindle slides, a spring surrounding said spindle and engaging said stop, a brake rigging, and means connecting said brake rigging to said spindle, and adapted when the brake is operated, to exert a vertical pressure on said spindle for causing simultaneously the compression of said spring and the raising of the body and load in such manner that the total braking effort, other things being equal varies with the total weight of the vehicle automatically and in accordance with a predetermined law.

3. In combination, a railway truck, a railway car body supported by said truck, a bogie spindle connecting said body and truck, a fixed stop through which said spindle slides, a spring for normally holding-said spindle in its lowest position, a double armed lever pivotally connected to said spindle, pivotally mounted bell-crank levers operatively connected to said double armed lever, a brake rigging, and means connecting said bell-crank lovers to said brake rigging.

In testimony whereof I affix my signature LOUIS EUGENE OHAMON. 

